1. Statement of the Technical Field
The invention relates to accessories for mobile devices. More particularly, this invention relates to an attachable external acoustic chamber for mobile devices to improve the audio performance and define a seamless, aesthetically pleasing mobile device casement profile.
2. Background of the Invention
The demand for mobile devices such as cellular telephones in recent years has been steadily increasing. As a result, the number of manufacturers of mobile devices and the competition among them has increased. This competition has forced mobile device designers to design mobile devices with additional features and capabilities to remain competitive. Typically, consumers prefer cellular telephones with longer talk time and standby time. The talk time and standby time depend on, among other things, the capacity of the battery that provides electrical power. There are many factors which determine the capacity of a battery for a mobile device. These factors include the materials used to manufacture the battery and the size of the battery. Accordingly, these factors affect the cost and weight of the battery. Mobile device designers must weigh all of these factors when selecting a battery for a mobile device for a particular model of mobile device.
One of the more recent popular features that have been incorporated into mobile devices is a loudspeaker. A loudspeaker allows the user to use the cellular telephone in a hands-free configuration without the use of headsets. Typically, in addition to the traditional mouthpiece and earpiece, a mobile device with a loudspeaker will have the loudspeaker in a front mounted or rear mounted configuration. The loudspeaker should have sufficient volume that it can be heard without holding the loudspeaker to the user's ear. Most mobile devices equipped with a loudspeaker feature have a switch which is depressed to activate the loudspeaker mode.
One drawback to incorporating the loudspeaker feature into a mobile device is that less volume is available for the loudspeaker in smaller sized mobile devices because of the smaller battery sizes that must be used. Thus, the function of the loudspeaker is less than optimal. One solution to this problem is for manufacturers of mobile devices to offer an aftermarket battery with greater power capacity that replaces the original battery. Such batteries are larger in size and are encased in a cover that typically extends further out of the battery chamber than the original battery. The result is a mobile device with an unsatisfactory casement profile.
Another drawback to a mobile device incorporating a loudspeaker is that the volume of the front or rear ported loudspeaker may not be optimal due to size constraints imposed on the phone ID.
There exists in the art an attempt to improve the audio performance of a cellular telephone. For example, in U.S. patent application no. 2005/0190941 A1, disclosed is a cellular telephone having a first opening for delivering voice on a shell. A printed circuit board (PCB) is disposed within an inner space enclosed by the shell and divides the inner space into a first acoustic room and a second acoustic room. A speaker is disposed within the first acoustic room and electrically connects the PCB. A through hole is formed on the PCB to communicate the first acoustic room and the second acoustic room to increase the size of total resonance chamber for improving resonance effect in low frequency voices. Furthermore, at least a second opening is formed on the shell to communicate the first acoustic room or the second acoustic room to the environment for flattening the resonance curve to improve the voice quality. However, the cellular phone disclosed does not have a loudspeaker and there is no attempt to improve the audio performance thereof.
Consequently, there exists a need in the art for a mobile device having an aesthetically pleasing casement profile when an extended capacity battery is installed in the battery cavity. There also exists a need in the art to improve the audio performance of a mobile device having a loudspeaker.